Sen. Mark Warner, D-Va., announced Tuesday that he will not seek a return to the governorship next year, setting up a likely bid for re-election in 2014.

“Over the last year, a lot of Virginians – Democrats, Republicans, and independents – have approached me and asked that I consider running for Governor a second time," Warner said in a statement. "I loved being governor, but I have a different job now — and it's here in the United States Senate."

It’s well-known that Warner enjoyed his time as governor from 2002 to 2006, and rumors of a potential return to Richmond have wafted through the Old Dominion political scene for the past year. As the most popular politician in the state, Warner would have been the heavy favorite in the gubernatorial race, and he is currently favored to win his first bid for re-election to the Senate.

Known as a moderate in the Senate and member of the "gang of six," Warner also kept up his public profile in the state this year. He went on several barnstorming tours with Democratic Sen.-elect Tim Kaine, who served as lieutenant governor under Warner and succeeded Warner in the governor’s mansion. Kaine defeated Republican George Allen this month for an open Senate seat by a surprisingly large 6-point margin, thanks in part to running as a potential partner to Warner in the Senate.

What’s unclear is which Republicans would consider taking on the state’s most imposing elected official, especially after Kaine's victory. It's no mystery that Republican Gov. Bob McDonnell, who is also popular and cannot seek re-election next year, would be the most viable option. But Virginia Republicans who spoke with Roll Call were skeptical that he would jeopardize his promising political career by taking on Warner, who would be tough to beat.

“Certainly at this point in time, Bob McDonnell and Mark Warner are the two strongest politicians in the state, but it’s tough to decide to go run against the other heavyweight on the other side of the fence,” veteran Republican strategist Boyd Marcus said. “Who knows what the situation will be in two years."

McDonnell spokesman Tucker Martin said the governor “has one focus and one focus only: serving as the governor of the commonwealth for the next 14 months.”

Warner’s decision was not a surprise in Virginia political circles. The make-up of the Virginia General Assembly has become far more Republican since Warner was in Richmond, and the number of Republicans still there who supported his tax increase compromise can be counted on one hand.

Warner conceded as much in an interview with The Associated Press last week. “You can’t just put the band back together,” he said. “Circumstances in Richmond and other things have changed.”

Still, the gubernatorial race could not move forward without official word from the state’s top Democrat. Virginia is one of two states to elect its governor in the year immediately following a presidential election, and candidates from both parties had already entered the race.

Warner told Democrats not to await his decision, so former Democratic National Committee Chairman Terry McAuliffe announced his candidacy days after the Nov. 6 elections. McAuliffe, a close friend of President Bill Clinton, lost in the Democratic primary in the 2009 gubernatorial race.

The top Republican contenders have been known for some time. Lt. Gov. Bill Bolling, who ran for re-election in 2009 instead of challenging McDonnell, will face Attorney General Ken Cuccinelli in a state party convention next year.

A Quinnipiac University poll released last week found that Warner led both Republicans by at least 20 points. Despite low approval ratings for Congress overall, 60 percent of those surveyed approved of the job Warner is doing.